Developer tank for strips of film



-May 31, 1938. HAGEN 2,119,230

DEVELOPER TANK FOR STRIPS OF FILM Filed June 29, 19556 IOa '5, INVENTOR.Paul. Ha EN WA TORNEYS.

fig. 5'

Patented May 31, 1938 PATENT OFFICE DEVELOPER TANK FOB STRIPS OF FILMPaul Hagen, Brooklyn,

.N. Y.; Margaret Hagen administratrix of said Paul Hagen, deceasedApplication June 29, 1936, Serial No. 87,947

11 Claim.

This invention relates to new and useful improvements in a developertank for strips of film.

' For many years it has been the general practice to develop films indark'rooms illuminated with red lights. In the last few years verysensitive films have been made which become fogged with even red lights.As a result, special variations of red lights and green lights have beenemployed.

With the innovation of miniature cameras the necessity for perfectlydeveloped films has greatly increased since it is customary to makeenlarged prints from the miniature films. Consequently, any defectspresent in the small films are greatly exaggerated, and even theslightest bit of fog may be prominently noticed on the enlargedphotograph. As a result of this many professiopal and amateurphotographers develop the highly sensitive film in totally dark rooms.This is extremely diflicult since one must depend exclusively upon one'ssense of touch.

This invention proposes the construction of a developer tank which islight proof and into which the films may be engaged and thereafter passthrough the various stages of developing without any exposurewhatsoever. Of course, it is necessary that this developer tank be usedin a dark room, but its advantages resides in the fact that the filmsare subjected only for a short time to any possible fogging, andthereafter is developed, fixed, washed, etc. without any furtherpossibility of light reaching them.

A further advantage gained by this arrangement resides in the fact thatthe films, during the greater portion of the developing, etc. are notmanually handled and consequently are not subjected to scratches andother damaging marks.

In order to insulate the developer tank from light it inadvertently isalso insulated from the free passage of air and consequently I havediscovered that the chemical processes during the developing and fixingof the films generates sufficient heat to slightly damage the films. Forexample, the bubbling caused by the chemical reaction has atendency todeposit on the film and produce defects. The invention thereforeproposes the provision of a cooling system for maintaining thetemperature within the developer tank at a pre-determined degree.

The invention also proposes an arrangement whereby the film may beeasily mounted within the developer tank in proper position-merely bythe sense of touch without the necessity of any light whatsoever withinthe dark room. Specifi- (Cl. ss sos) cally, it is proposed to provide adrum with a spiral track upon it upon which the film may be easilyengaged by the sense of touch. Further, it is proposed to so arrange thedrum and the track that the film is exposed to the developing, fixing,and other solutions. It is proposed to support the film at its edges sothat both sides are exposed to the solutions. Prior constructionsrequired that the film be supported with the emulsion side outwards asthe inner sides rested against covering parts.

A further object of the invention resides in the provision of a novelstirrer associated with the film carrying drum and capable of stirringthe liquid within the developer tank and so insure good developing.

Another object of the invention resides in providing the developer tankwith a removable cover so that the film may be engaged into the tank.Furthermore, it is proposed to provide light proof joints to prevent thepassage of light into the tank.

Another object of the invention proposes a. very small inlet-to the tankassociated with a light shield so that liquid may be poured therein.Also, it is proposed to provide an arrangement for draining off theliquid. It is thus possible to use the developer, fixer, and othersolutions in succession without opening the developer tank.

For further comprehension of the invention, and of the objects andadvantages thereof, refer ence will be had to the following descriptionand accompanying drawing, and to the appended claims in which thevarious novel features of the invention are more particularly set forth.

In the accompanying drawing forming a material part of this disclosure:-

Fig. 1 is a perspective view of a developer tank for strips of filmconstructed according to this invention.

Fig. 2 is a vertical longitudinal sectional view of Fig. 1.

Fig. 3 is a fragmentary longitudinal sectional view of the back righthand corner of the tank shown in Fig. 1.

Fig. 4 is a transverse sectional view taken on the line 4-4 of Fig. 2.

The developer tank for strips of film; according to this invention,comprises a light proof tank Ill having a removable light proof coverIlla. A rotatable film carrier ii is arranged within the tank upon whichstrips of film I2 may be engaged in a totally dark room. A means isprovided for driving the carrier ll.

At the bottom of the tank there is an auxiliary compartment l3 throughwhich refrigerating liquid may be circulated. This compartment has aninlet tube 14 and an outlet tube i5 for hoses to supply and to draw offcirculating refrigerant. At the bottom of the tank [0 there is a faucet15 through which the liquid in the tank it) may be drawn off. The coverIlla is provided with a small neck I8 normally closed by a lightproofplug [1. It is through this neck l6 that liquid may be supplied into thetank. A light shield l8 comprises several baiiles painted black or otherlight absorbent colors, and arranged transversely across the neck i6 andwithin the cover. It is thus possible to pour liquids through the neckinto the tank without light being capable of reaching the film which ishoused within the tank.

The joints between the cover Ilia and the tank H) are lightproof. Theyare formed by a flange I 9 surrounding the edge of the tank and engaginginto a corresponding receiving recess in the edge of the cover. Otherlightproof joints and materials may be used-to lightproof the tank. Athermometer 20 is arranged within the tank I!) and extends through thecover Illa. to the exterior. The exterior portion 20' of the thermometeris protected by a shield 2|. It is possible to read the temperature ofthe liquid whenever desired.

The carrier ll comprises a pair of end discs Ila and Ill) connectedtogether with longitudinal strips llc. A spiral track 22 is mountedaround the longitudinal strips llc. This track has a central raisedportion 22a forming side shoulders upon which the film I2 may bemounted. Thus, the film is supported at its edges and the intermediateportions thereof are free and do not touch any parts so as to be exposedto the liquid.

The end discs Ha and Ill) are perforated in order that liquid may passthrough them. The disc Ila is provided with a shaft 23 which issupported on a bearing 24 mounted upon the inner wall of the tank. Thedisc Ilb is provided with a shaft 25 which extends through a lightprooibearing 26 to the exterior. This lightproof bearing comprises a block26a having edge recesses engaging the edges of a cutout iOc formed inthe side wall of the tank 10. A lightproof packing gland 26b is mountedon the side of the block 26a. The bearing 24 is one from which the shaft23 may be readily lifted. Similarly, the block 26a may be lifted fromthe tank. It is thus possible to remove the film carrier when desired. Apulley 28 is mounted on the extended end of the shaft 25 by which thedevice may be mechanically or manually driven. The driving means for thepulley, is not shown on the drawing, as it forms no part of theinvention.

An elastic band 30 is attached upon one of the strips I la and supportsa clip 3i adapted to engage one end of the film l2. Another clip 32 forengaging the other end of the film is supported on a band 33 mountedupon one of the strips He and another portion of the carrier.

A mixer for the liquid within the tank is provided and consists oftrough members 34 extended between the discs Ila and llb at a slightinclination from end to end so that as the carrier rotates the troughmembers will lift up the liquid from one side of the tank and convey itto the other side of the tank, which produces a stirring action. Thetrough members, as shown in Fig. 4, are arranged to lift the liquid whenthe carrier rotates clockwise, as seen in this figure.

The operation of the device is as follows: The

tank i0 is empty. The developer tank is in a totally dark room Withoutany light whatsoever. The cover Illa is removed and the carrier H isaccessible. The strip of film is then opened from its lightproof packageand one end connected with the clip 3|; then the film is Wound on thecarrier by manually turning it and winding it between the spiral track22.- The end of the film is held by engaging the clamp 32 on it. Thecover 10a is engaged upon the tank. The film is now within a lightprooftank.

A red light or a green light, depending upon the type of film, may nowbe turned on in the developing room. The plug I! may be removed. afunnel engaged into the neck 16, and developing solution poured into thetank. The plug I1 is then immediately replaced. The driving means forthe carrier isturned on and the carrier will rotate in the developingsolution. For miniature films it is desirable that the developing actionprogress very slowly and the developer may be permitted to remain inaction for twenty minutes, more or less, as required. During the turningof the carrier I I the film will be continuously immersed in thedeveloping solution. The developing solution will be efficlently stirredby the rough members 34 picking up portions thereof and causing them tomove from one end to the other end of the tank. Should the temperaturewithin the developing tank start to rise, a source of cold water may beconnected to the nipples l4 and i5 and circulated through thecompartment l3. In this manner the temperature will be correct withinthe developing tank.

After the developing is completed the faucet l5 may be opened and theliquid drawn off. The other solutions necessary for developing, fixing,etc., are then placed into the tank one at a time for the requiredlength of time, similar to the developer solution previously described.The carrier is operated as required for the various solutions. When thefilm has been completely developed, fixed, washed, etc., the cover Illamay be removed from the tank and the film I2 removed.

While I have illustrated and described my invention with some degree ofparticularity, 1. realize that in practice various alterations thereinmay be made. I therefore reserve the right and privilege of changing theform of the details of construction or otherwise altering thearrangement of the correlated parts without departing from the spirit orthe scope of the appended claims.

Having thus described my invention, what I claim as new and desire tosecure by United States Letters Patent is:-

1. A developer tank for films comprising an en closed lightproof tankhaving a removable lightproof cover, a movable film carrier within saidtank upon which film may be engaged in a totally dark room, means fordriving said carrier, said carrier comprising a pair of spaced discsconnected together with strips and a spiral track mounted upon saidstrips, said spiral track having a raised central portion formingshoulders for supporting the edges of the film.

2. A developer tank for films comprising an enclosed lightproof tankhaving a removable lightproof cover, a movable film carrier within saidtank upon which film may be engaged in a totally dark room, means fordriving said carrier, said carrier comprising a pair of spaced discsconnected together with strips and a spiral track mounted upon saidstrips, said spiral track having a raised central portion formingshoulders for supporting the edges of the film, and trough membersmounted between said end discs and arranged with an inclination from oneend to the other and adapted to stir liquid within said tank.

3. A combination stirrer and film carrier comprising a cylindricalframe, a spiral track mounted thereon and having shoulders for receivingthe edges of a film to support the film so that both sides areunobstructed, means for holding said film on said track, and a troughmember within said frame located at an inclination so that one end ishigher than the other and capable of stirring when said cylindricalframe is rotated.

4. A combination stirrer and film carrier comprising a cylindricalframe, a spiral track mounted thereon and having shoulders for receivingthe edges of a film to support the film so that both'sldes areunobstructed, means for holding said film on said track, and a troughmember within said frame located at an inclination so that one end ishigher than the other and capable of stirring when said cylindricalframe is rotated, and means for rotating said cylindrical frame.

5. In a developer tank for films, a lightproof tank member having anopening, a bearing block member removably mounted on an edge portion ofsaid opening, lightproof elements for the adjacent edge portions of saidbearing block and said tank member, a drive shaft engaging through saidbearing, a film carrier removably mounted within said tank andoperatively connected with said drive shaft, a lightproof cover memberfor said tank, and flange elements on certain of said members engageablewith a receiving recess on the other of said members and surroundingsaid opening for lightproofing the developer tank when the cover isclosed.

6. In a developer tank for films, a lightproof tank member having anopening, a bearing block member removably mounted on an edge portion ofsaid opening a drive shaft engaging through said bearing, a film carrierremovably mounted within said tank and operatively connected with saiddrive shaft, a lightproof cover member for said tank, a flange oncertain of said members engageable with a receiving recess on the otherof said members and surrounding said opening for lightproofing thedeveloper tank when the cover is closed, and a light baille element onsaid bearing block member cooperative with a complementary light bafileelement on said tank member for lightproofing the junction of saidbearing block and tank.

7. In a developer tank for films, a lightproof tank member having anopening, a bearing block member removably mounted on an edge portion ofsaid opening, a drive shaft engaging through said bearing, a filmcarrier removably mounted within said tank and operatively connectedwith said drive shaft, a lightproof cover member for said tank, a flangeon certain of said members engageable with a receiving recess on theother of said members and surrounding said opening for lightproofing thedeveloper tank when the cover is closed, and a light bafile element onsaid bearing block member cooperative with a complementary light bafileelement on said tank member for lightproofing the junction of saidbearing block and tank, said elements comprising a fiange engaging arecess.

8- In a developer tank for films, a lightproof tank for housing a filmcarrier and developing solutions and other solutions, a neck element onsaid tank through which liquid may be supplied thereto, a plug forclosing said neck element, and a light shield within said tank in thevicinity of said neck element.

9. In'a developer tank for films, a lightproof tank for housing a filmcarrier and developing solutions and other solutions, a neck element onsaid tank through which liquid may be supplied thereto, a plug forclosing said neck element, and a light shield within said tank in thevicinity of said neck element, and comprising several bai'lies paintedblack or other light absorbent color and arranged transversely acrosssaid neck element.

10. A developer tank for films comprising an enclosed lightproof tankhaving a removable lightproof cover, a movable film carrier within saidtank upon which film may be engaged in a totally dark room, means fordriving said carrier, said carrier comprising a cylindrical structure, aspiral track mounted on the periphery thereof, means for holding one endof a strip of film on a portion of said cylindrical structure so thatthe strip of film may be upon said cylindrical structure with its edgessupported on said track, and a means for holding the other end of saidfilm upon said cylindrical structure.

11. A developer tank for films comprising an enclosed lightproof tankhaving a removable lightproof cover, a movable film carrier within saidtank upon which film may be engaged in a totally dark room, means fordriving said carrier, said carrier comprising a cylindrical structure, aspiral track mounted on the periphery thereof, means for holding one endof a strip of film on a portion of said cylindrical structure so thatthe strip of film may be upon said cylindrical structure with its edgessupported on said track, and a means for holding the other end of saidfilm upon said cylindrical structure, said spiral track having a raisedcentral portion forming shoulders for supporting the edges of said film.

PAUL HAGEN.

